Cats live longer than dogs. The cats most likely to live the longest are well loved random-bred cats. The cats most likely to live the shortest are ill-treated purebreds. Cross-breeding results in hybrid vigor. Inbreeding results in health problems including immune system problems and congenital defects. I realise that is a gross simplification but it does make the point. A well loved moggie might live to 20 years and more. Purebreds are considered old at 7 years of age by some people.
Whereas people suffer decline in old age for about the last third of their lives, cat old age lasts for the final tenth of their lives. They become less flexible, more addicted to routine and sometimes suffer from dementia, which amongst other things can result in nighttime howling due to confusion. The lack of flexibility results in poor coat condition. Very old cats require more intensive human caretaking just like very old people.
Neutered tom cats live longer than unneutered toms by about three years. There are two reasons (a) they have less fights (b) they are more resistant to infection.
Do you know why cats live longer than dogs? There appears to be no one simple answer. My theory is that the major reason is that the percentage of purebred dogs to the overall dog population is higher than for cats. Apparently 55% of dogs are purebred. Twenty-five percent of dogs at shelters are purebred, which is much higher than for cats.
It is difficult to find figures for cats but my guess is that the percentage of purebred cats is very low, well below 10%, perhaps around 3%.
Accepting that purebred companion animals shorter lives than moggies, this explains the difference in longevity between domestic cats and dogs. Of course, feral and stray cats live much shorter lives on average.
A 20 year old cat is almost 100 years old in human terms. Cats reach maturity in 1/15th of their lifespan while humans do the same in 1/5th – slower.
It can be quite tricky to judge a cat’s age. I wrote a page about it. You’ll find different views from different sources about the oldest feline. One cat had named “Puss” had a lifespan of 36 years (1903-1939).
Although I have stated that Siamese cats are the world’s most unhealthy cat, one visitor to PoC wrote about “Jellbean”, a Siamese who lived to 30 years of age.